Fatigue analysis of stay cables on the long-span bridges under combined action of traffic and wind

As the construction of long-span bridges such as cable-stayed bridges increases worldwide, maintaining bridge serviceability and operability has become an important issue in civil engineering. The stay cable is a principal component of cable-stayed bridges and is generally lightly damped and intrinsically vulnerable to vibration. Excessive vibrations in stay cables can potentially cause long-term fatigue accumulation and serviceability issues. Previous studies have mainly focused on the mitigation of cable vibration within an acceptable operational level, while little attention has been paid to the quantitative assessment of serviceability enhancement provided by vibration control. This study accordingly proposed and evaluated a serviceability assessment method for stay cables equipped with vibration control. Cable serviceability failure was defined according to the range of acceptable cable responses provided in most bridge design codes. The cable serviceability failure probability was then determined by means of the first-passage problem using VanMarcke’s approximation. The proposed approach effectively allows the probability of serviceability failure to be calculated depending on the properties of any installed vibration control method. To demonstrate the proposed method, the stay cables of the Second Jindo Bridge in South Korea were evaluated and the analysis results accurately reflected cable behavior during a known wind event and show that the appropriate selection of vibration control method and properties can effectively reduce the probability of serviceability failure.

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Experimental Investigation on Vortex-Induced Vibration Mitigation of Stay Cables in Long-Span Bridges Equipped with Damped Crossties

Journal of Aerospace Engineering ◽

10.1061/(asce)as.1943-5525.0001061 ◽

2019 ◽

Vol 32 (5) ◽

pp. 04019072

Author(s):

Min Liu ◽

Wenhan Yang ◽

Wenli Chen ◽

Huigang Xiao ◽

Hui Li

Keyword(s):

Experimental Investigation ◽

Vibration Mitigation ◽

Vortex Induced Vibration ◽

Long Span Bridges ◽

Long Span ◽

Stay Cables

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Experimental Study of Environmental Conditions on In-Situ Engineered Cementitious Composites-Steel Deck Interface

Applied Sciences ◽

10.3390/app10062123 ◽

2020 ◽

Vol 10 (6) ◽

pp. 2123 ◽

Cited By ~ 1

Author(s):

Shuyin Wu ◽

Xiaoyin Sun ◽

Jun Yang ◽

Ruochong Yang ◽

Jipeng Zhu

Keyword(s):

Interfacial Strength ◽

Epoxy Adhesive ◽

Interface Failure ◽

Hydrothermal Aging ◽

Long Span Bridges ◽

Freeze Thaw ◽

Long Span ◽

Bonding Technology ◽

Combined Action ◽

Steel Deck

In this study, engineered cementitious composite (ECC) was used as a deck paving for long-span bridges. The feasibility of using an epoxy adhesive to achieve wet-bonding between a steel deck and cast-in-place ECC was evaluated. The shear and pull-off tests were conducted to evaluate the effects of freeze-thaw cycles and hydrothermal aging on interfacial properties. The test results indicate that the interfacial strength decreases with an increase in the number of freeze-thaw cycles and the duration of hydrothermal aging. Based on an inclined shear test, a criterion for interface failure under the combined action of shear and compression is also proposed. Wet-bonding technology might promote the application of ECC in the surfacing system for orthotropic steel deck bridge and further extend the service life of a bridge structure.

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Automated Real-Time Assessment of Stay-Cable Serviceability Using Smart Sensors

Applied Sciences ◽

10.3390/app9204469 ◽

2019 ◽

Vol 9 (20) ◽

pp. 4469 ◽

Cited By ~ 2

Author(s):

Seunghoo Jeong ◽

Young-Joo Lee ◽

Do Hyoung Shin ◽

Sung-Han Sim

Keyword(s):

Real Time ◽

Damping Ratio ◽

Assessment System ◽

Smart Sensors ◽

Stay Cable ◽

Long Span Bridges ◽

Long Span ◽

Stay Cables ◽

High Flexibility ◽

Cable Stayed Bridges

The number of cable-stayed bridges being built worldwide has been increasing owing to the increasing demand for long-span bridges. As the stay-cable is one of critical load-carrying members of cable-stayed bridges, its maintenance has become a significant issue. The stay-cable has an inherently low damping ratio with high flexibility, which makes it vulnerable to vibrations owing to wind, rain, and traffic. Excessive vibration of the stay-cable can cause long-term fatigue problems in the stay-cable as well as the cable-stayed bridge. Therefore, civil engineers are required to carry out maintenance measures on stay-cables as a high priority. For the maintenance of the stay-cables, an automated real-time serviceability assessment system using wireless smart sensors was developed in this study. When the displacement of the cable in the mid-span exceeds either the upper or the lower bound provided in most bridge design codes, it is considered as a serviceability failure. The system developed in this study features embedded on-board processing, including the measurement of acceleration, estimation of displacement from measured acceleration, serviceability assessment, and monitoring through wireless communication. A series of laboratory tests were carried out to verify the performance of the developed system.

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Moving Load and Fatigue Analysis of a Long Span High Speed Railway Bridge

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.629.403 ◽

2012 ◽

Vol 629 ◽

pp. 403-408 ◽

Cited By ~ 3

Author(s):

Alessio Pipinato

Keyword(s):

High Speed ◽

Moving Load ◽

Optimal Solution ◽

Fatigue Analysis ◽

Suspension Bridges ◽

Railway Bridge ◽

Structural Shape ◽

High Speed Railway ◽

Long Span Bridges ◽

Long Span

Long span bridges, as cable-stayed and suspension bridges, have gained much popularity in recent decades for their structural shape, efficient use of materials and other optimal solution. A new phase is starting with main span lengths going over thousands of meter. As a matter of fact, small size substructures are required, the development of efficient construction techniques are growing on and faster progress in the FEM and design are evident. Ever since the dramatic collapse of the first examples of such long span structures, as the Tacoma Narrows Bridge in 1940, much attention has been given to the dynamic behavior of these structures. In this paper a moving load analysis performed on a cable stayed high speed railway bridge is presented together with a fatigue analysis of the cable stays, discussed according to the Italian code verification procedure.

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Feasibility study of wind tunnel aeroelastic tests on bridges with floating towers

IABSE Congress, New York, New York 2019: The Evolving Metropolis ◽

10.2749/newyork.2019.2650 ◽

2019 ◽

Author(s):

Tommaso Argentini ◽

Claudio Montagna ◽

Daniele Rocchi

Keyword(s):

Wind Tunnel ◽

Feasibility Study ◽

Experimental Validation ◽

Numerical Models ◽

Design Solution ◽

Long Span Bridges ◽

Long Span ◽

Actuation System ◽

Floating Offshore Wind Turbines ◽

Combined Action

Floating towers are an innovative design solution for long-span bridges crossing deep waters, where grounded towers are not applicable. This kind of structural solution brings about challenging issues related to the design of such structures exposed to the combined action of aerodynamic forces and hydrodynamic forces. One of the major issues is the experimental validation of numerical models to simulate the structural dynamics, based on hybrid codes joining aero-elastic and hydro-elastic interactions.This paper presents a feasibility study of wind-tunnel aeroelastic tests, where the submerged part of the bridge is simulated by Hardware-In-the-Loop (HIL) technology: actuators simulates the motion of the floater due to the combined action of the hydrodynamic loads on the floater (numerically simulated in real time) and of the aerodynamic and inertial loads transmitted by the tower (measured by a 6-components dynamometer). A similar HIL testing device has been developed at POLIMI in the field of floating offshore wind turbines, and it is likely to be applied to long-span bridges, as a tool for the experimental validation of complex numerical hybrid approaches.The opportunities offered by this technology will be discussed in the paper, working out a numerical example where the full-scale response of a FEM of the full-bridge is simulated and then it is scaled in order to assess the feasibility of aeroelastic tests in wind tunnel, with a focus on the characteristics of the actuation system for the tower base: necessary of degrees of freedom, amplitude and bandwidth of motion and force.

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